Class AbstractOSProcess

java.lang.Object

oshi.software.common.AbstractOSProcess

All Implemented Interfaces:

OSProcess

Direct Known Subclasses:

AixOSProcess, DragonFlyBsdOSProcess, FreeBsdOSProcess, LinuxOSProcess, MacOSProcessJNA, NetBsdOSProcess, OpenBsdOSProcess, SolarisOSProcess, WindowsOSProcess

@ThreadSafe
public abstract class AbstractOSProcess
extends Object
implements OSProcess

A process is an instance of a computer program that is being executed. It contains the program code and its current activity. Depending on the operating system (OS), a process may be made up of multiple threads of execution that execute instructions concurrently.

Nested Class Summary

Nested classes/interfaces inherited from interface OSProcess

OSProcess.State

Modifier and Type	Interface	Description
static enum	OSProcess.State	Process and Thread Execution States

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractOSProcess(int pid)	Creates an AbstractOSProcess for the given process ID.

Method Summary

Modifier and Type	Method	Description
double	getProcessCpuLoadBetweenTicks(OSProcess priorSnapshot)	Gets CPU usage of this process since a previous snapshot of the same process, provided as a parameter.
double	getProcessCpuLoadCumulative()	Gets cumulative CPU usage of this process.
int	getProcessID()	Gets the process ID.
String	toString()

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface OSProcess

getAffinityMask, getArguments, getBitness, getBytesRead, getBytesWritten, getCommandLine, getContextSwitches, getCurrentWorkingDirectory, getEnvironmentVariables, getGroup, getGroupID, getHardOpenFileLimit, getInvoluntaryContextSwitches, getKernelTime, getMajorFaults, getMinorFaults, getName, getOpenFiles, getParentProcessID, getPath, getPriority, getPrivateResidentMemory, getResidentMemory, getSoftOpenFileLimit, getStartTime, getState, getThreadCount, getThreadDetails, getUpTime, getUser, getUserID, getUserTime, getVirtualSize, getVoluntaryContextSwitches, updateAttributes

Modifier and Type	Method	Description
long	getAffinityMask()	Gets the process affinity mask for this process.
List<String>	getArguments()	Makes a best effort attempt to get a list of the the command-line arguments of the process.
int	getBitness()	Attempts to get the bitness (32 or 64) of the process.
long	getBytesRead()	Gets the bytes read by the process.
long	getBytesWritten()	Gets the bytes written by the process.
String	getCommandLine()	Gets the process command line used to start the process, including arguments if available to be determined.
default long	getContextSwitches()	A snapshot of the context switches the process has done, equal to the sum of OSProcess.getVoluntaryContextSwitches() and OSProcess.getInvoluntaryContextSwitches() on platforms that provide the split.
String	getCurrentWorkingDirectory()	Makes a best effort attempt to obtain the current working directory for the process.
Map<String,String>	getEnvironmentVariables()	Makes a best effort attempt to obtain the environment variables of the process.
String	getGroup()	Gets the group under which the process is executing.
String	getGroupID()	Gets the group id under which the process is executing.
long	getHardOpenFileLimit()	Gets the hard limit for open file handles (or network connections) that belong to the given process.
default long	getInvoluntaryContextSwitches()	The number of involuntary context switches the process has made.
long	getKernelTime()	Gets kernel/system (privileged) time used by the process.
default long	getMajorFaults()	Gets the number of major (hard) faults the process has made which have required loading a memory page from disk.
default long	getMinorFaults()	Gets the number of minor (soft) faults the process has made which have not required loading a memory page from disk.
String	getName()	Gets the name of the process, often the executable program.
long	getOpenFiles()	Gets the number of open file handles (or network connections) that belongs to the process.
int	getParentProcessID()	Gets the process ID of this process's parent.
String	getPath()	Gets the full filesystem path of the executing process.
int	getPriority()	Gets the priority of this process.
default long	getPrivateResidentMemory()	Returns an estimate of the portion of physical memory (RAM) uniquely attributed to this process.
long	getResidentMemory()	Returns the total amount of physical memory (RAM) currently mapped to the process's address space.
long	getSoftOpenFileLimit()	Gets the soft limit for open file handles (or network connections) of the given process.
long	getStartTime()	Gets the process start time.
OSProcess.State	getState()	Gets the process state.
int	getThreadCount()	Gets the number of threads being executed by this process.
List<OSThread>	getThreadDetails()	Retrieves the threads of the process and their details.
long	getUpTime()	Gets up time / elapsed time since the process started.
String	getUser()	Gets the user name of the process owner.
String	getUserID()	Gets the user id of the process owner.
long	getUserTime()	Gets user time used by the process.
long	getVirtualSize()	Gets the Virtual Memory Size (VSZ).
default long	getVoluntaryContextSwitches()	The number of voluntary context switches the process has made.
boolean	updateAttributes()	Attempts to update process attributes.

Constructor Details

AbstractOSProcess

protected AbstractOSProcess(int pid)

Creates an AbstractOSProcess for the given process ID.

Parameters:

pid - the process ID

Method Details

getProcessID

public int getProcessID()

Description copied from interface: OSProcess

Gets the process ID.

While this is a 32-bit value, it is unsigned on Windows and in extremely rare circumstances may return a negative value.

Specified by:

getProcessID in interface OSProcess

Returns:

the processID.

getProcessCpuLoadCumulative

public double getProcessCpuLoadCumulative()

Description copied from interface: OSProcess

Gets cumulative CPU usage of this process.

This calculation sums CPU ticks across all processors and may exceed 100% for multi-threaded processes. This is consistent with the cumulative CPU presented by the "top" command on Linux/Unix machines.

Specified by:

getProcessCpuLoadCumulative in interface OSProcess

Returns:

The proportion of up time that the process was executing in kernel or user mode.

getProcessCpuLoadBetweenTicks

public double getProcessCpuLoadBetweenTicks(OSProcess priorSnapshot)

Description copied from interface: OSProcess

Gets CPU usage of this process since a previous snapshot of the same process, provided as a parameter.

This calculation sums CPU ticks across all processors and may exceed 100% for multi-threaded processes. This is consistent with process usage calculations on Linux/Unix machines, but should be divided by the number of logical processors to match the value displayed by the Windows Task Manager.

The accuracy of this calculation is dependent on both the number of threads on which the process is executing, and the precision of the Operating System's tick counters. A polling interval of at least a few seconds is recommended.

Usage example:

Map<Integer, OSProcess> priorSnapshot = new HashMap<>();
while (monitoring) {
    for (OSProcess p : os.getProcesses(null, null, 0)) {
        double cpu = p.getProcessCpuLoadBetweenTicks(priorSnapshot.get(p.getProcessID()));
        priorSnapshot.put(p.getProcessID(), p);
    }
    Thread.sleep(2000);
}

Specified by:

getProcessCpuLoadBetweenTicks in interface OSProcess

Parameters:

priorSnapshot - An OSProcess object containing statistics for this same process collected at a prior point in time. May be null.

Returns:

If the prior snapshot is for the same process at a prior point in time, the proportion of elapsed up time between the current process snapshot and the previous one that the process was executing in kernel or user mode. Returns cumulative load otherwise.

toString

public String toString()

Overrides:

toString in class Object